There are only a few animals who find an owner or a new home.
"飼い主や新しい家が見つかる動物はごくわずかです" は英語でThere are only a few animals who find an owner or a new home.といえます。他- The number of animals who are able to find an owner or a new home are very few.- There are very few animals who are able to find an owner or a new home.
Very few animals in shelters end up going back to their owner or finding a new home.
詳しい状況がわかりませんが、次のようにもう少し情報を加えると自然な言い方ができます。ーVery few animals in shelters end up going back to their owner or finding a new home.「シェルターの非常に少ない動物が飼い主のもとに戻るか新しい家を見つける」＝「飼い主や新しい家が見つかる動物はごくわずかだ」to end up ~ing で「最終的に〜する」ご参考まで！
アメリカ合衆国 
カナダ 
